Department of Human Nutritional Sciences, University of Manitoba, Canadian Centre for Agri-Food Research in Health and Medicine, Winnipeg, Canada R3T 2N2.
Department of Human Nutritional Sciences, University of Manitoba, Canadian Centre for Agri-Food Research in Health and Medicine, Winnipeg, Canada R3T 2N2.
J Nutr Biochem. 2018 Jul;57:228-237. doi: 10.1016/j.jnutbio.2018.04.002. Epub 2018 Apr 18.
There is much data on the effects of dietary n-3 fatty acids on tissue fatty acid compositions, but comparable comprehensive data on their oxygenated metabolites (oxylipins) is limited. The effects of providing female and male rats with diets high in α-linolenic acid (ALA), EPA or DHA for 6 weeks on oxylipins and fatty acids in kidney, liver and serum were therefore examined. The oxylipin profile generally reflected fatty acids, but it also revealed unique effects of individual n-3 fatty acids that were not apparent from fatty acid data alone. Dietary ALA increased renal and serum DHA oxylipins even though DHA itself did not increase, while dietary EPA did not increase DHA oxylipins in kidney or liver, suggesting that high EPA may inhibit this conversion. Oxylipin data generally corroborated fatty acid data that indicated that DHA can be retroconverted to EPA and that further retroconversion to ALA is limited. Dietary n-3 fatty acids decreased n-6 fatty acids and their oxylipins (except linoleic acid and its oxylipins), in order of effectiveness of DHA > EPA > ALA, with some exceptions: several arachidonic acid oxylipins modified at carbon 15 were not lower in all three sites, and EPA had a greater effect on 12-hydroxy-eicosatetraenoic acid and its metabolites in the liver. Oxylipins were predominantly higher in males, which was not reflective of fatty acids. Tissue-specific oxylipin profiles, therefore, provide further information on individual dietary n-3 fatty acid and sex effects that may help explain their unique physiological effects and have implications for dietary recommendations.
关于膳食 n-3 脂肪酸对组织脂肪酸组成的影响已有大量数据，但关于其氧化代谢物（类二十烷酸）的可比综合数据有限。因此，本研究检测了为雌性和雄性大鼠提供富含 α-亚麻酸（ALA）、EPA 或 DHA 的饮食 6 周对肾脏、肝脏和血清中的类二十烷酸和脂肪酸的影响。类二十烷酸谱通常反映了脂肪酸，但它也揭示了个别 n-3 脂肪酸的独特影响，仅从脂肪酸数据无法看出。膳食 ALA 增加了肾脏和血清 DHA 类二十烷酸，尽管 DHA 本身没有增加，而膳食 EPA 并未增加肾脏或肝脏中的 DHA 类二十烷酸，这表明高 EPA 可能抑制这种转化。类二十烷酸数据通常与脂肪酸数据相符，表明 DHA 可逆向转化为 EPA，并且进一步逆向转化为 ALA 受到限制。膳食 n-3 脂肪酸按 DHA > EPA > ALA 的有效性降低了 n-6 脂肪酸及其类二十烷酸（除了亚油酸及其类二十烷酸），但也有一些例外：在所有三个部位，碳 15 处修饰的几种花生四烯酸类二十烷酸并未降低，并且 EPA 对肝脏中 12-羟基二十碳四烯酸及其代谢物的影响更大。类二十烷酸主要在雄性中更高，这与脂肪酸不同。因此，组织特异性类二十烷酸谱提供了关于个别膳食 n-3 脂肪酸和性别影响的进一步信息，这可能有助于解释它们独特的生理影响，并对饮食建议有影响。
